Why Troubleshooting VoIP Issues is Hard

01 Mar 2005

The people who work in tech support for companies like BroadVoice have a hery hard job. They have to troubleshoot to discover if one of the myriad of problems with audio quality or making and receiving calls is a problem with their network or “something else.” The fact, there is a lot of something elses that could be causing problems.

First, let’s talk about the telephone handset itself. Many people, myself included, employ a cordless phone. It runs at 2.4 Ghz like my WLAN gear. That can cause audio problems as that is prone to dropouts and the like, especially if you also run 2.4Ghz Wireless LAN in your house like I do. Similarly, people also use wireless headsets. Even if they don’t use 2.4Ghz, there are potential issues with dropouts and poor sound quality. The person at the other end might also be experiencing this phoenomenon with their equipment.

While unlikely, it is possible that the Analog Telephone Adapter (e.g Sipura, Grandstream) might also be introducing some sort of audio problem (e.g. defective hardware, impedence settings don’t match what the handset expects).

The ethernet cable between the Analog Telephone Adapter and router/switch might be causing intermittent packet loss (e.g. because it has a short). The router/switch might also be experiencing a problem (configuration or otherwise)

This doesn’t even take into account the possible networking issues that might be occuring (e.g. congested link between you and the VoIP provider).

While the above isn’t a complete list of what could be going wrong, it gives you an idea of why it’s difficult to narrow down the exact cause of audio problems on VoIP calls. With all the different points of failure, it’s amazing it works as well as it does.